What
When a tool's output is too long and gets cut short (truncated), Claude Code can now attach a truncationNote: a short explanatory message added after the shortened content, separated from it by a blank line. The note only appears when truncation actually happened and a note was provided.
Why
This gives a clearer signal when output has been shortened, instead of leaving the reader to guess why the content stops abruptly or seems incomplete.
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubt
The finding does not say which tools supply a truncationNote or what the note's wording looks like in practice.